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The study examines the impact of the incorporation of quantum-sized nickel (Ni) nanoparticles in TiO2 (titanium dioxide) matrix at 1%, 3%, and 5% weight percentages by straightforward, easy, and potentially effective synthesis strategy of direct doping. The structural, morphological, optical, and electrical characterization studies of synthesized films are systematically done and the photovoltaic, photocatalytic applications are evaluated. The integration of nickel into TiO2 influences its photovoltaic properties by enhancing the open-circuit voltage (Voc). However, higher concentrations lead to increased recombination and defects, decreasing efficiency. On conducting photocatalytic studies, TiO2 doped with 1 wt. % nickel exhibits superior photocatalytic efficiency, surpassing that of undoped TiO2. This improvement in photovoltaic and photocatalytic performance is attributed to better charge separation and reduced recombination. However, optimizing nickel levels is crucial for maximizing benefits for the applications using the performed synthesis strategy. [ABSTRACT FROM AUTHOR]

Rare-earth ion doped oxide thin films integrated on silicon substrates provide a route toward scalable, chip-scale platforms for quantum coherent devices. Erbium-doped TiO 2 is an attractive candidate: the Er 3 + optical transition is compatible with C-band optical fiber communications, while TiO 2 is an insulating dielectric compatible with silicon process technology. Through structural and optical studies of Er-doped TiO 2 thin films grown via molecular beam deposition on silicon, SrTiO 3 , and sapphire substrates, we have explored the impact of polycrystallinity and microstructure on the optical properties of the Er emission. Comparing polycrystalline TiO 2 (rutile)/Si with single-crystalline TiO 2 (rutile)/r-sapphire and polycrystalline TiO 2 (anatase)/Si with single-crystalline TiO 2 (anatase)/ SrTiO 3 , we observe that the inhomogeneous linewidth (Γ inh) of the most prominent peak in the Er spectrum (the Y 1 – Z 1 transition, 1520 and 1533 nm in rutile and anatase TiO 2) is significantly narrower in the polycrystalline case. This implies a relative insensitivity to extended structural defects and grain boundaries in such films (as opposed to, e.g., point defects). We show that the growth of an undoped, underlying TiO 2 buffer on Si can reduce Γ inh by a factor of 4–5. Expectedly, Γ inh also reduces with decreasing Er concentrations: we observe a ∼ 2 order of magnitude reduction from ∼ 1000 ppm Er to ∼ 10 ppm Er. Γ inh then gets limited to a residual value of ∼ 5 GHz that is insensitive to further reduction in the Er concentration. Based upon the above results, we argue that the optical properties in these thin films are limited by the presence of high "grown-in" point defect concentrations. [ABSTRACT FROM AUTHOR]

A deterministic, bright, room-temperature stable single-photon source (SPS) has been a major demand in the field of quantum photonics. Here, using computational and analytical techniques, we showed that the Mie-scattering moments of an all-dielectric cavity-cum-antenna help in shaping the spontaneous emission process of an embedded point-dipole emitter, the nanodiamond-based NV − and SiV color centers here. Our resonator-cum-antenna design comprises two top and bottom TiO 2 cylinders with a sandwiched polyvinyl alcohol (PVA) layer enclosing the nanodiamond crystal. The Cartesian multi-polar decomposition of the Mie-scattering moments of the sandwiched PVA layer (enclosing the dipole emitter) with subwavelength scale thickness showed strong electric-dipole (ED) resonance. This resulted in significant field confinement, making the PVA layer to act as a cavity, providing a Purcell enhancement of more than an order of magnitude for all dipole orientations. The top and bottom TiO 2 cylinders were observed to act as an antenna, and the far-field radiation pattern of the embedded dipole-emitter is controlled by the Mie-scattering moments of the TiO 2 cylinders. The radiation directionality along the vertical directions was found to be maximum at the Kerker point (electric dipole moment, ED = magnetic dipole moment), the collection efficiency (CE) being about 80%. For dipole emission coupled to the antenna, the quantum efficiency was observed to increase to a high value of 0.98 for nanodiamond NV − center, very close to an ideal case of purely radiative emission. Our scheme is shown to be universal and can be applied to any solid-state-based quantum emitters, for generating on-demand SPS for quantum-photonic applications. [ABSTRACT FROM AUTHOR]

We studied the photoluminescence decay kinetics of three nanosized anatase TiO2 photocatalysts (particle diameter: 7, 25, or 200 nm) at the pico- and nanosecond timescales for elucidating the origin of the luminescence. Luminescence spectra from these photocatalysts obtained under steady-state excitation conditions comprised green luminescence that decayed on the picosecond timescale and red luminescence that persisted at the nanosecond timescale. Among the photocatalysts with different sizes, there were marked differences in the rate of luminescence decay at the picosecond timescale (<600 ps), although the spectral shapes were comparable. The similarity in the spectral shape indicated that self-trapped excitons (STEs) directly populated in the bulk of the particle by light excitation emit the luminescence in a picosecond timescale, and the difference in the rate of luminescence decay originated from the quenching at the particle surface. Furthermore, we theoretically considered excitation light intensity dependence on the quantum yield of the luminescence and found that the quenching reaction was not limited by the diffusion of the STEs but by the reaction at the particle surface. Both the spectral shape and time-evolution of the red luminescence from the deep trapped excitons in the nanosecond timescale varied among the photocatalysts, suggesting that the trap sites in different photocatalysts have different characteristics with respect to luminescence. Therefore, the relation between trap states and photocatalytic activity will be elucidated from the red luminescence study. [ABSTRACT FROM AUTHOR]

Ti-doped In 2 O 3 thin films with varying Ti contents are prepared by partial reactive co-sputtering using ceramic In 2 O 3 and metallic Ti targets and characterized by in situ x-ray photoelectron spectroscopy, electrical conductivity, and Hall-effect measurements. For a substrate temperature of 400 ° C , the carrier concentration increases faster than the Ti content and saturates at ≈ 7.4 × 10 20 c m − 3 . Based on these results, it is suggested that Ti does not directly act as donor in In 2 O 3 but is rather forming TiO 2 precipitates and that the related scavenging of oxygen generates oxygen vacancies in In 2 O 3 as origin of doping. Neutralization of oxygen vacancies is, therefore, suggested to be origin of the limitation of the carrier concentration in Ti-doped In 2 O 3 films. [ABSTRACT FROM AUTHOR]

The increasing demand for functional nanodevices in sustainable energy applications necessitates the development of innovative approaches. In this study, we present the fabrication and characterization of three-dimensional (3D) structures coated with titanium dioxide (TiO 2) nanorods (NRs). These novel devices are created through the integration of four distinct techniques, multi-photon lithography, post-thermal treatment, pulsed laser deposition, and an aqueous chemical growth, enabling their unique properties and functionalities in photocatalysis. The photocatalytic performance of the 3D devices is evaluated through the degradation of organic pollutants, such as methylene blue and stearic acid, showcasing their efficiency in reducing pollutant concentrations. The devices demonstrate a remarkable decomposition coefficient (k = 0.059 min − 1 ), highlighting their enhanced photocatalytic efficiency. Additionally, we propose a rapid fabrication technique using 3D holographic printing to create large-area TiO 2 -coated micro-structured photocatalytic devices at the mesoscale regime. This approach increases the active surface area, further enhancing the devices' photocatalytic capabilities. By combining additive micro-manufacturing, TiO 2 NR coating, and holographic printing, our work introduces a promising avenue for the development of advanced nanodevices with superior photocatalytic performance in sustainable energy applications. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the radiation enhancement effects of ultrasound-stimulated microbubbles (USMB) with X-rays and nanoparticles on pancreatic cancer cells in vitro. Methods: Sonazoid™ microbubbles were used for USMB treatment with a commercially available ultrasound unit. The characterization of the microbubbles before and after ultrasound exposure with different mechanical parameters was evaluated microscopically. Two pancreatic cancer cell lines, MIAPaCa-2 and PANC-1, were treated with different concentrations of microbubbles in combination with 150 kVp X-rays and hydrogen peroxide-modified titanium dioxide nanoparticles. Cell viability was evaluated using a water-soluble tetrazolium dye and a colony formation assay. In addition, intracellular reactive oxygen species (ROS) induced by the combined treatment were assessed. Results: The number of burst microbubbles increased with ultrasound's higher mechanical index and the exposure time. A significant radiation enhancement effect with a significant increase in ROS levels was observed in MIAPaCa-2 cells treated with USMB and 6 Gy X-rays, whereas it was not significant in PANC-1 cells treated with the same. When a higher concentration of USMB was applied with X-rays, no radiation enhancement effects were observed in either cell line. Moreover, there was no radiation enhancement effect by USMB between cells treated with and without nanoparticles. Conclusions: The results indicate that USMB treatment can additively enhance the therapeutic efficacy of radiation therapy on pancreatic cancer cells, while the synergistic enhancement effects are likely to be cell type and microbubble concentration dependent. In addition, USMB did not improve the efficacy of nanoparticle-induced radiosensitization in the current setting. Keywords: Microbubbles, nanoparticles, radiation therapy, radiosensitizer, ultrasound, Author(s): Masao Nakayama (corresponding author) [1,2,3]; Ayaha Noda [4]; Hiroaki Akasaka [1,5]; Takahiro Tominaga [4]; Giulia McCorkell [2]; Moshi Geso [2]; Ryohei Sasaki [1] INTRODUCTION Microbubbles have been used clinically [...]

Non-metallic modified TiO 2 has been proven to be an effective approach for promoting photocatalytic performance. However, the catalytic mechanism remains largely unclear. In this work, we discovered that the N atom occupied interstitial positions or displaced O atom in bulk exhibited remarkable photocatalytic hydrogen evolution activity in the absence of oxygen vacancies (Ov). Furthermore, the presence of Ov at the surface will introduce the Ti3+ species and resulting in a downward shift of the d-band center. Importantly, the impurity energy levels coupled with Ti (3d), O (2p), C (2p), and N (2p) orbitals below the conduction band further facilitate the separation of photogenerated e−/h+ pairs and further enhance light absorption, the optimal system exhibiting a ΔG of −0.02 eV. Subsequently, the synthesis of the predicted C, N co-doped TiO 2 was carried out. The photocatalytic hydrogen evolution rate reached 795 μmolg−1h−1 at 400 nm. This work provides unprecedented atomistic insights into the photocatalytic hydrogen evolution reaction. The doping of C and N atoms leads to strong p-d band coupling, which accelerates the rapid migration of charge carriers from the bulk to the surface, and the electrons localize at the O sites, where they undergo the photocatalytic hydrogen evolution reactions, respectively. [Display omitted] • Obtained the optimal position of C,N co-doped TiO 2. • The importance of the synergistic effect of C,N for the photocatalytic activity of TiO 2 is demonstrated. • The combination of DFU + U and experiment demonstrates the high activity of C,N co-doped TiO 2. • The strong d-p-band interaction accelerates carrier separation. [ABSTRACT FROM AUTHOR]

Pt nanoparticles (NPs) loaded on TiO 2 photocatalyst as cocatalyst is well-known for significantly enhancing photocatalytic H 2 production from an aqueous methanol solution since Pt NPs in contact with the TiO 2 surface can improve the charge separation by accepting photoexcited electrons. In this study, another catalytic role of Pt NPs was clearly evidenced by a simple method, using a flow reactor and gas mixture of methanol and water in argon carrier, in which TiO 2 photocatalyst and separately supported Pt NPs are located without physical contact. It was demonstrated that hydrogen radical species, generated on the TiO 2 photocatalyst, are capable of migrating through a quartz wool layer of several millimeters in length and reach the Pt NPs on alumina support, where coupling of the hydrogen radical to form H 2 molecules is catalytically promoted by the Pt NPs. [Display omitted] • Mixture of TiO 2 and Pt/Al 2 O 3 promotes photocatalytic H 2 production and selectivity. • Experiments with a flow reactor evidenced catalytic role of Pt cocatalyst. • Pt NPs catalyze coupling of hydrogen radicals to form H 2. • Hydrogen radical can migrate for millimeter scale in gaseous reaction mixture. • Shorter distance between TiO 2 and Pt NPs gives higher H 2 production rate. [ABSTRACT FROM AUTHOR]

Here, a composite material comprised of inner ternary TiO 2 /CaTi 4 O 9 /CaTiO 3 nanoparticles and outer reduced graphene oxide (RGO) layer was fabricated and further applied as the photocatalyst for hydrogen production and Cr(VI) reduction. The PL result shows that the intimate interface between RGO and TiO 2 /CaTi 4 O 9 /CaTiO 3 composite can effectively promote the transfer of electrons (e - ), thus reducing its recombination on TiO 2 /CaTi 4 O 9 /CaTiO 3 , which provides much more electrons for H 2 production and the Cr (VI) reduction reactions. A remarkable improvement in H 2 production and Cr (VI) reduction were achieved over TiO 2 /CaTi 4 O 9 /CaTiO 3 modified with RGO. Notably, with optimum RGO content, the 1.0 wt%RGO-TiO 2 /CaTi 4 O 9 /CaTiO 3 showed the best H 2 production performance of 34.78 mmol h−1 g−1, which is 15.09 and 6.86 times higher than TiO 2 and CaTiO 3 , respectively. Moreover, an excellent Cr (VI) reduction rate of 53.79% was also achieved over 1.0 wt%RGO-TiO 2 /CaTi 4 O 9 /CaTiO 3 , which is 4.82 and 5.55 times higher than that of TiO 2 and CaTiO 3 , respectively. • Reduced graphene oxide (RGO) surface-modified TiO 2 /CaTi 4 O 9 /CaTiO 3 composite was synthesized. • The electron transfer to the reduced graphene oxide (RGO) and reduced charge recombination has been investigated. • RGO-TiO 2 /CaTi 4 O 9 /CaTiO 3 composite showed excellent photocatalytic performance in both H 2 production and Cr(VI) reduction. • A dual-Z-scheme was established in the ternary composite. [ABSTRACT FROM AUTHOR]

The current research introduces a novel in-situ and visibly-active heterojunction formation concept to fabricate a sustainable antimicrobial cementitious material. To achieve this, cement mortar incorporating iron-rich industrial waste products (FWPs) was outer-coated with photocatalyst Titanium dioxide (TiO 2). The proposed technique forms a novel surface-active Fe 2 TiO 5 heterojunction oxide layer, which considerably improves the photocatalytic and antimicrobial properties of TiO 2 under the visible spectrum of light. Primarily, the study evaluated the structural suitability of the developed iron-rich cementitious material in terms of its durability and strength properties. The findings indicate that the iron-rich cementitious material performed better than conventional cementitious material. After this, the effectiveness and novelty of the proposed research were examined, such that the Fe 2 TiO 5 photocomposite was subjected to detailed microscopic investigations such as XRD, HRTEM, UV-DRS, XPS, FESEM, etc. The results verified the production of the inherent Fe 2 TiO 5 heterojunction through the presence of Fe in the photocatalyst TiO 2 lattice via the formation of ITO complex bonds. It also revealed that the Fe 2 TiO 5 photocomposite functions effectively under visible light with an energy band gap of 2.57 eV. The antimicrobial activity of the Fe 2 TiO 5 photocomposite was also assessed by neutralizing E.coli bioaerosols. The disinfection results indicated that the Fe 2 TiO 5 photocomposite exhibits excellent antimicrobial properties. It achieved 69.33 % and 95–98 % antibacterial efficiency under dark and visible light, respectively. Thus, the study establishes a Fe 2 TiO 5 photocomposite material that combines photocatalytic and antimicrobial properties, making it suitable for use as a sustainable building material. Also, it contributes to environmental sustainability by promoting a circular economy and green building practices. • The design and manufacturing of an antibacterial and photocatalytic sustainable building material. • Utilization of cement mortar incorporating FWPs to make the surface active Fe 2 TiO 5 heterojunction photocomposite. • Fe from FWPs enhances TiO 2 's photocatalytic action via the inherent concept of Fe 2 TiO 5 heterojunction formation. • The Fe 2 TiO 5 photocomposite potentially inactivates E.coli bioaerosols under visible light. [ABSTRACT FROM AUTHOR]

The pure nanostructured anatase titanium dioxide (TiO 2) and subsequent nitrogen–doped derivatives (TiO 2–x N x; where, x = 0.005, 0.01, 0.05) were synthesized by sol–gel auto–combustion technique. XRD analysis confirms the formation of pure anatase phase of TiO 2 up to doping of 1 mol% (x = 0.01) of nitrogen having tetragonal structure with space group of I 4 1 / amd whereas an additional monoclinic phase of TiO 2 –B was observed at 5 mol% of nitrogen doping in TiO 2. This sample has smallest crystallite size of ∼4.7 ± 0.2 nm corresponding to TiO 2 –B phase and ∼12.0 ± 0.1 nm corresponding to anatase phase. XRD also reveals that the crystallite size of all other samples having pure anatase phase ranges between ∼8.7 ± 0.1 nm & 13.9 ± 0.1 nm. The crystalline phase revealed from XRD of all samples was further supported by the Raman analysis. The direct optical band gap of pure TiO 2 (∼3.4 eV) was reduced non–monotonically after nitrogen doping in the ranges from ∼2.8 eV (TiO 1.95 N 0.05) to ∼2.0 eV (TiO 1.99 N 0.01). FTIR spectra confirm the metal oxide bond formation, surface adsorption of water molecules and presence of residual hydroxyl group in all crystalline samples. HRTEM analysis validates the coexistence of secondary phase of TiO 2 –B along with anatase phase of TiO 2 in studied highest doped sample (TiO 1.95 N 0.05) including its broader particle size distribution as compared to pure TiO 2. The electrical studies reveal that the highest values of dielectric constant and ac conductivity can be realized for pure TiO 2 and at 1 mol% (x = 0.01) of nitrogen doping, among all the studied nitrogen doped samples. • Influence of nitrogen doping on the physical properties of anatase TiO 2. • Highest nitrogen doping level in N:TiO 2 possesses structurally dual phase nature. • TEM images also validate the presence of dual phases within the N:TiO 2 lattice. • Nonmonotonic control of optical band gap can be realized via doping of N in TiO 2. [ABSTRACT FROM AUTHOR]

Ceramic aerogels exhibit an extremely high porosity, low weight, and exceptionally low thermal conductivity, making them suitable as insulating materials for use in challenging environments. The widespread application of conventional ceramic aerogels is typically constrained by the fragile nature of the material and its high-temperature infrared radiation transparency. Here, we successfully prepared SiTiOC/PS/TiO 2 hybrid aerogels by effectively synthesizing them using polyvinyl alcohol (PVA) as the carbon skeleton and reinforcing them with polystyrene microspheres (PS) and PAN nanofibers loaded with TiO 2 (TiO 2 /PAN NFs), and TiO 2 /PAN NFs as shading material. This was achieved through a combination of the polymer precursor transformation method, sol-gel method, and techniques such as freeze-drying and electrostatic spinning. The findings indicated that the fabricated SiTiOC/PS/TiO 2 hybrid aerogels exhibited a lightweight structure, exceptionally high infrared reflectivity, remarkably low thermal conductivity, and outstanding mechanical characteristics. The successful synthesis of the SiTiOC/PS/TiO 2 hybrid aerogels offers a novel approach for advancing the production of various thermal insulation materials. [ABSTRACT FROM AUTHOR]

The slag-metal reaction between traditional CaO-SiO 2 -CaF 2 -Na 2 O-based slag and high-titanium steel deteriorates the performance of the mold flux, negatively affecting the surface quality of the slab and causing issues in continuous casting. To maintain the stability of slag properties after the slag-metal interaction, BaO and Li 2 O were added to the mold flux as a potential new slag system of the BaO-CaO-SiO 2 -TiO 2 -CaF 2 -Li 2 O-Na 2 O seven-component slag for the continuous casting of high titanium steel. In this study, the effects of the BaO/CaO ratio on the structure and properties of the seven-component slag were examined using molecular dynamics simulation and Raman spectroscopy, and the effect of the BaO content on the amphoteric behavior of TiO 2 was also investigated. With the gradual substitution of CaO by BaO, the melt's basicity increases, and TiO 2 transforms from acidic TiⅤ to alkaline TiⅥ. Simultaneously, the addition of BaO promotes the conversion of O b into O f and O nb , resulting in a simplified melt structure. The continuous increase in content of structural units Q Si 0 and Q Si 1 , along with the continuous decrease in content of Q Si 3 and Q Si 4 , further elucidates this phenomenon. Hence, it can be inferred that BaO primarily functions as a depolymerizing agent within the network structure of the melt. [ABSTRACT FROM AUTHOR]

This study is the first attempt to examine the electrochemical properties of TiO 2 composite with Fe 3 O 4 thin film. In our analysis, X-Ray diffraction (XRD) confirms the formation of Fe 3 O 4 on TiO 2. Fourier Transform Infrared Spectroscopy (FT-IR) and Raman spectroscopy confirmed the functional groups. The UV–Vis spectroscopy analysis shows that the addition of Fe 3 O 4 results in decrease in optical band gap. Our Cyclic Voltammetry (CV) results demonstrate that, under steady state conditions, the behaviors of TiO 2 and Fe 3 O 4 /TiO 2 electrodes regarding ion adsorption and charge transmission vary. Pseudocapacitive effects and charge transfer affects the functionality of the TiO 2 electrode, whereas two-layer capacitance effects primarily control the response of the Fe 3 O 4 /TiO 2 electrode. Numerous factors, including ion diffusion, rate capability, charge transfer, and series resistance, can be directly determined using electrochemical impedance spectroscopy (EIS). The experimental results and analysis presented in this work brings to light the significance of Fe 3 O 4 in the electrochemical response of an electrode-electrolyte interface. [ABSTRACT FROM AUTHOR]

Marine water‐lubricated bearings have the advantages of environmental friendliness and long replacement cycle. However, when under the complex lubrication circumstance, the frictional and vibrational behaviors of water‐lubricated bearing always dissipate the mechanical energy output from the ship's diesel engine. Aiming at this problem and combining with previous research findings, in this paper, ceramic balls with similar mechanical properties to ship's main shaft were selected as the friction counterpart to simulate the operating conditions of marine water‐lubricated bearing. Meanwhile, dual nanoparticles of tungsten disulfide (WS2) and titanium dioxide (TiO2) were used to modify ultra‐high molecular weight polyethylene (UHMWPE) bearing material. The tribological and vibrational properties of the prepared composites were carefully investigated. The results showed that compared to pure UHMWPE, with the synergistic effect of 0.75 wt% WS2 and 0.9 wt% TiO2, the frictional and vibrational behaviors of the composites were reduced by 43.3% and 42.7%. Mechanical testing and microscopic characterization revealed the enhancement mechanism of these nanoparticles on UHMWPE. This study proposed a design strategy on marine water‐lubricated bearings for engineering application. [ABSTRACT FROM AUTHOR]

In this work, the Dy 2 O 3 -Al 2 O 3 -SiO 2 (DASN) and Dy 2 O 3 -Al 2 O 3 -SiO 2 -TiO 2 (DAST) glass fillers were used for joining alumina ceramic. During the cooling process of the alumina/DASN/alumina joints, Dy 2 Si 2 O 7 and Al 2 O 3 were precipitated simultaneously and gradually grown. As a result, voids were formed due to the poor flowability of the glass ceramic filler and the large density difference between the glass filler and Dy 2 Si 2 O 7 crystals. On the contrary, the addition of TiO 2 altered the sequence of the crystalline phase precipitation during the cooling process. During cooling from the joining temperature (1450 °C) to 1100 °C, only Dy 2 Si 2 O 7 was formed in the brazing seam. Simultaneously, the flowing glass phase was able to fill the spaces caused by the density differences. When the growth of Dy 2 Si 2 O 7 phase ceased, the Al 2 O 3 phase began to precipitate. Therefore, the voids caused by density differences can be eliminated in the alumina/DAST/alumina joints with high crystallinity. The optimal flexural strength of alumina/DAST/alumina joints tested at room temperature and 1000 °C reached 350 MPa and 158 MPa, respectively. [ABSTRACT FROM AUTHOR]

TiO 2 -based colossal dielectric ceramics have emerged as a prominent research focus in recent years. However, their further applications have been constrained by several key limitations, including the requirement of high sintering temperature (>1400 °C), relatively high dielectric loss (>0.05, 1 kHz), and temperature stability (<200 °C). This study reports rutile (In 0.5 Ta 0.5) 0.1 Ti 0.87 O 1.88 F 0.12 ceramics at 1220 °C sintering using 12 % InF 3 as the acceptor In3+ source, which exhibits a colossal dielectric constant (1.1 × 105) and an ultra-low dielectric loss (0.0071) at 1 kHz and room temperature, even loss values below 0.04 (20 Hz - 100 kHz). Notably, the thermal stabilities (10 kHz, 100 kHz) simultaneously satisfy X9E (Δε r /ε 25 °C ≤ ±4.7 %) above 300 °C. F − not only supplies electrons to enhance the semiconductivity of grains, but also decreases the oxygen vacancy and average grain size (270 ± 12.53 nm) to improve grain boundaries resistances, which reduces dielectric loss and enhances frequency and temperature stabilities. As a result, the dielectric mechanism is mainly related to internal barrier layer capacitor (IBLC) and high grain boundary resistance. Therefore, this strategy provides a creative design for developing TiO 2 -based ceramics. [ABSTRACT FROM AUTHOR]

In this paper, erbium-doped gadolinium oxide rare earth oxide nanoparticles (Gd 2 O 3 :Er3+) with good light absorption capacity from the visible to the infrared region were prepared by polyol method, and then compounded with TiO 2 by hydrothermal method. SEM, TEM, XPS, UV–vis and electrochemical workstation were used to study the morphology, structure, UV–vis light absorption and photoelectrochemical (PEC) properties of Gd 2 O 3 :Er3+/TiO 2. The results showed that the Gd 2 O 3 :Er3+ spherical nanoparticles with a particle size of about 15 nm were uniformly distributed on the surface of the TiO 2 nanorod array, and the Gd 2 O 3 :Er3+/TiO 2 nanocomposites had good light absorption capacity in the infrared region. Furthermore, the photocurrent densities of Gd 2 O 3 /TiO 2 and Gd 2 O 3 :Er3+/TiO 2 were 2.08 and 2.75 times higher than those of TiO 2 , respectively, manifesting that the broadening of infrared light absorption can improve the PEC property of TiO 2. Meanwhile, the DFT calculation results showed that the energy band of Gd 2 O 3 :Er3+/TiO 2 was significantly narrower than that of TiO 2 , indicating that Gd 2 O 3 :Er3+/TiO 2 had a redshift phenomenon of UV–vis absorption. The calculation results of state density showed that the f orbital of Gd 2 O 3 :Er3+ intersected with the d orbital of TiO 2 , indicating that there is an electron transfer between Gd 2 O 3 :Er3+ and TiO 2. Erbium-doped gadolinium oxide rare earth oxide nanoparticles (Gd 2 O 3 :Er3+) with good light absorption capacity from the visible to the infrared region were prepared by polyol method, and then compounded with TiO 2 by hydrothermal method. Both theoretical and experimental results confirmed the extension of optical absorption into the infrared range and the charge transfer from Gd 2 O 3 :Er3+ to the TiO 2 surface, facilitating electron-hole separation and reducing charge recombination rate. [Display omitted] [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO 2) is commonly used additive to improve the strength, hardness and coefficient of expansion properties of vitrified bonds. In this work, TiO 2 nanobelts were prepared through hydrothermal method, and the effect of TiO 2 nanobelts content on the microstructure and physical properties of vitrified bonds and vitrified bond CBN composites were systematically investigated. When the content of 0.2 wt% TiO 2 nanobelts and sintered at 660 °C, as-prepared nano-vitrified bonds exhibited the beneficial performance improvement. Specifically, the obtained coefficient of thermal expansion, flexural strength, microindentation hardness, and mobility are 5.37 × 10−6 °C−1, 85.96 MPa, 853.19 MPa, and 140.6 %, respectively. Moreover, the vitrified bonds with 0.2 wt% TiO 2 nanobelts addition is further used to optimize the performance of cubic boron nitride (CBN) composites. When sintered at 720 °C, the CBN composite samples depicted the excellent flexural strength, rockwell, porosity, and grinding ratio of 63.27 MPa, 61.5 HRB, 48.9 %, and 22.3, respectively. It can be attributed to the positive contribution of nano-vitrified bonds on the physical properties of CBN composites. This work is expected to contribute to the research on improving the performance of vitrified bonds with nano additives, and further obtain excellent performance nano-vitrified bond materials for the design and manufacturing of high-performance superhard abrasive tools. [ABSTRACT FROM AUTHOR]

The study addresses the limited fracture toughness of Al 2 O 3 ceramics by developing graphene-TiO 2 reinforced alumina nanocomposites through pressing. Mechanical properties, including hardness, fracture toughness, and elasticity, were examined, alongside the structural characterization via XRD analysis and microstructure evaluation using SEM. Cytotoxicity and cell adhesion tests were conducted for in vitro biological evaluation. The inclusion of a graphene additive led to a nearly threefold increase in fracture toughness, reaching up to 8.161 MPa m1/2. Graphene doping induced a discernible shift to lower angles in the XRD pattern, revealing the presence of Al 2 O 3 , Al 2 TiO 5 , and TiO 2 phases. Samples immersed in artificial body fluid for 14 days exhibited minimal ion release, with Titanium ion below 0.001 mg/L and aluminum ion below 0.05 mg/L, indicating a lack of significant ion release. The cytotoxic activity of the samples against NIH/3T3 cells was assessed through Alamar Blue analysis, revealing no significant change in cell viability after 48 h of exposure. [ABSTRACT FROM AUTHOR]

Aiming to further improve the properties of novel MgAl 2 O 4 -Si 3 N 4 ceramic used as solar thermal absorbing material in concentrating solar power, effects of Sm 2 O 3 and TiO 2 on performance of the composites were investigated especially the mechanisms of different additives on microstructure and high temperature stability. The results show that both additives can accelerate sintering, reduce sintering temperature, improve the density and high temperature stability via liquid phase sintering mechanism. Besides, TiO 2 can form displacement solid solution with Al 2 O 3 to promote the sintering process. Sm 2 O 3 is more conducive to improving the bending strength due to its function of increasing the length diameter ratio of β-Si 3 N 4. TiO 2 is more favorable for improving solar absorption owing to the distinctive absorption spectrum and large number of cation vacancy caused by substitution of Al3+ by Ti4+. MgAl 2 O 4 -Si 3 N 4 composites with Sm 2 O 3 and TiO 2 additives have better performance than MgAl 2 O 4 -Si 3 N 4 , Si 3 N 4 and SiC ceramics prepared via the same procedure, which makes it a certain choice for solar thermal absorbing material. [ABSTRACT FROM AUTHOR]

Coatings are utilized to enhance the surface properties of materials. This study aimed to modify the TiN coating with a novel sandwich-zigzag intermediate layer and delve into the intricate damage mechanisms under harsh corrosion-erosion coupling environments. Due to the infiltration of NaCl into the coating and the subsequent formation of TiO 2 , the sandwich-zigzag TiN coatings exhibited a reduction in mechanical behavior and erosion resistance when exposed to salt spray at 550 °C for 50 h. Moreover, the erosion rates of the as-corroded TiN coatings displayed an opposite trend compared to that of the as-deposited coatings, showing that the erosion rate was highest at the erosion angle of 30°. Nevertheless, the presence of the zigzag-TiN intermediate layer benefited the coating by preventing stress accumulation and heterogeneous interface. This ultimately improved the erosion resistance of the coatings by more than 2 times at universal erosion angle compared to that of the substrates under the synergistic effects of corrosion and erosion. [ABSTRACT FROM AUTHOR]

Electrochemical anodization, under a constant voltage of 45 V and for 15, 30, and 45 min, was performed to fabricate highly ordered TiO 2 nanotubes. Depending on the processing paramters, the diameter of the TiO 2 nanotubes was found to be around 95 ± 6 nm, while the thickness of TNT layer exhibited a change with anodizing time, varying from 1 to 4 μm. Subsequent to the anodization α-Fe 2 O 3 /TiO 2 heterogeneous structure was created by the spin coating of iron precursor based solutions on TiO 2 nanotubes. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were utilized to ascertain the phase structure and morphology of TiO 2 nanotubes. The change of optical band gap values depending on the processing parameters was calculated using UV–Vis spectrophotometer data. The photocatalytic performances of the samples, namely the degradation rates and kinetics, were evaluated by examining the photodegradation of methylene blue (MB). The (TC15) sample, obtained by anodizing for 15 min and decorated with α-Fe 2 O 3 , exhibited the highest photocatalytic activity, with a degradation efficiency of 70 % at the end of 7 h of light exposure. On the other hand, the inhibition percentages of bacterial growth were examined and it was seen that the TC30 sample with the highest value was 88.89 % for E.coli bacteria and 70.57 % for S.aureus. To assess the mechanism of antimicrobial activity, ROS (Reactive Oxygen Species) Analysis were perfomed on T30 and TC30 groups and the ROS amount of TC30 was higher than T30. According to the results of the L929 mouse fibroblast cytotoxicity experiment with indirect contact according to ISO 10993-5 standards, all samples showed a successful performance in terms of cell viability. The cell viability of TC15 was higher in comparison to the control group. [ABSTRACT FROM AUTHOR]

Adding titanium oxide has become a common practice in modern blast furnace operating procedures. The blast furnace slag is based on the CaO–MgO–Al 2 O 3 –SiO 2 –TiO 2 low titanium slag system rather than CaO–MgO–Al 2 O 3 –SiO 2 system. Phase equilibria in the CaO–SiO 2 –Al 2 O 3 –MgO–TiO 2 system in the low-TiO 2 part have been experimentally determined by means of high temperature equilibration and quenching technique followed by electron probe X-ray microanalysis. Introducing a small quantity of titanium-bearing materials can lower the liquidus temperature. The TiO 2 content in the slag should be controlled below 4.6 wt%, otherwise it will enter the perovskite phase region where the liquidus temperatures increases rapidly. The compositions of the solid solutions corresponding to the liquidus have been precisely measured and should be utilized for developing the thermodynamic database. [ABSTRACT FROM AUTHOR]

[Display omitted] The present paper reports the fabrication of novel types of hybrid fibrous photocatalysts by combining block copolymer (BCP) templating, sol–gel processing, and coaxial electrospinning techniques. Coaxial electrospinning produces core–shell nanofibers (NFs), which are converted into hollow porous TiO 2 NFs using an oxidative calcination step. Hybrid BCP micelles comprising a single plasmonic nanoparticle (NP) in their core and thereof derived silica-coated core–shell particles are utilized as precursors to generate yolk-shell type particulate inclusions in photocatalytically active NFs. The catalytic and photocatalytic activity of calcined NFs comprising different types of yolk-shell particles is systematically investigated and compared. Interestingly, calcined NFs comprising silica-coated yolk-shells demonstrate enhanced catalytic and photocatalytic performance despite the presence of silica shell separating plasmonic NP from the TiO 2 matrix. Electromagnetic simulations indicate that this enhancement is caused by a localized surface plasmon resonance and a confinement effect in silica-coated yolk-shells embedded in porous TiO 2 NFs. Utilization of the coaxially electrospun TiO 2 NFs in combination with yolk-shells comprising plasmonic NPs reveals to be a potent method for the photocatalytic decomposition of numerous pollutants. It is worth noting that this study stands as the first occurrence of combining yolk-shells (Au@void@SiO 2) with porous electrospun NFs (TiO 2) for photocatalytic purposes and gaining an understanding of plasmon and confinement effects for photocatalytic performance. This approach represents a promising route for fabricating highly active and up-scalable fibrous photocatalytic systems. [ABSTRACT FROM AUTHOR]

The laser-regulated mixed-phase TiO 2 efficiently enhances the hydrogenation or hydroxylization of nitrogen to form NH*/NOxOH*, thereby promoting electrochemical overall nitrogen fixation. [Display omitted] • Laser synthesis has achieved the fabrication of TiO 2 integrated electrodes with controllable phase sites. • The optimized mixed-phase TiO 2 can serve as both anode and cathode, achieving good nitrogen reduction and oxidation activity. • The rutile phase promotes nitrogen adsorption activation, while the anatase phase provides protons and reactive oxygen species. • A dual-electrode coupled system constructing by mixed-phase TiO 2 achieves a breakthrough in overall electrocatalytic nitrogen fixation. Traditional oxide electrocatalytic materials encounter significant challenges associated with sluggish reaction kinetics and formidable energy barriers for NH intermediates formation in electrocatalytic nitrogen fixation. The implementation of phase control emerges as an effective strategy to address these challenges. Herein, leveraging the energy localization of laser, this work achieved precise phase control of TiO 2. In the optimized material system, the rutile phase TiO 2 facilitates nitrogen adsorption, while the anatase phase TiO 2 provides proton sources and active oxygen species. The synergistic effect of the two phases effectively enhances the electrocatalytic activity for nitrogen reduction and oxidation, with an ammonia yield reaching ∼22.3 μg h-1 cm-2 and a nitrate yield reaching ∼60.9 μg h-1 cm-2. Furthermore, a coupled dual-electrode system with mixed-phase titanium dioxide as both the anode and cathode successfully achieved a breakthrough in electrochemical overall nitrogen fixation. This laser precision control strategy for manipulating phase sites lays the groundwork for designing efficient catalysts for energy conversion and even energy storage nanomaterials. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) has long been receiving attention as a promising material for enhancing the performance of photovoltaic devices due to its tunable optoelectronic properties. This paper reviews the utilization of TiO2 in recent photovoltaic applications, focusing primarily on its role as an optical material. The fundamental properties of TiO2 are reviewed, such as its wide bandgap and unique property of tunable refractive index. Furthermore, various strategies are discussed to harness the fundamental properties of TiO2 to improve light absorption and charge carrier generation within various photovoltaic devices. Overall, the pivotal role of TiO2 as an Earth‐abundant and non‐critical optical material is highlighted for future advances in the power conversion efficiency and viability of photovoltaic technologies, paving the way for future research and developments aimed at achieving sustainable and cost‐effective solar energy conversion. [ABSTRACT FROM AUTHOR]

This study focuses on improving the mechanical properties and microstructure of cement-based materials, which are crucial for the durability and safety of construction projects. Conventional cement, although commonly used, has certain limitations in terms of its mechanical strength and durability. Therefore, there is a requirement for innovative methods to enhance these properties. This study investigates the potential of nano-TiO2 (titanium dioxide) as an additive to overcome these limitations. The objective of this research is to perform a thorough experimental analysis to examine how different concentrations of nano-TiO2 impact the mechanical performance and microstructural changes in cement paste and mortar. The study examines the influence of nano-TiO2 on the compressive and flexural strengths of cementitious materials. It also explores how nano-TiO2 modifies the microstructure to enhance compactness and resilience. The results suggest that incorporating nano-TiO2 into cement leads to a substantial improvement in both compressive and flexural strengths. This enhancement is particularly notable when the nano-TiO2 concentration is at an optimal level of 1.0% by weight. The SEM and XRD analyses demonstrate that this concentration enhances the microstructure by decreasing voids and facilitating the development of C-S-H crystals. However, excessive concentration may have negative consequences, such as the creation of extra empty spaces. The results indicate that nano-TiO2 has considerable promise in enhancing cement-based materials, thereby aiding the advancement of construction materials that are more long-lasting and effective. This study contributes to the knowledge of how nano-TiO2 improves cement and emphasizes its potential uses in the construction sector. [ABSTRACT FROM AUTHOR]

The application of polymer blends such as epoxidized natural rubber (ENR) and polyvinyl chloride (PVC) in immobilizing titanium dioxide (TiO2) photocatalysts has enticed many researchers. However, the presence of polymer limits the photocatalytic activity by hindering the surface‐active site of the immobilized TiO2. In this study, photoetching treatment with the presence of dye was successfully applied on the immobilized TiO2/ENR/PVC (TEP) to enhance the photocatalytic and photoelectrochemical (PEC) performance. Priorly, a dip coating technique was used to immobilize the TEP. The dye photoetching treatment was performed for several cycles to determine the reusability of the immobilized TEP. Furthermore, it demonstrated a significant enhancement of photocatalytic activity at which the best performance with the pseudo‐first‐order rate constant, k value of 0.1483 min−1 at the 13th cycle. The nonetched, photoetched TEP without dye and dye photoetched TEP have been characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), and PEC. It is believed that the dye photoetched TEP will produce a good photocatalytic activity and PEC performance due to the presence of dye stimulant during the photoetching treatment. [ABSTRACT FROM AUTHOR]

The performance of Poly(lactic acid) (PLA) composites reinforced with functionalized titanium dioxide (TiO2) nanoparticles in rutile and anatase crystalline phases were systematically investigated. The results underline that the incorporation of TiO2, regardless of its crystalline structure, significantly enhances PLA's crystallinity by 85%. Notably, rutile TiO2, when functionalized with higher glutaric acid concentrations, was an effective crystallinity booster by 95%, passing from 20.39% to 39.58% crystallinity for the PLA/TiO2 R20 + 10% system. Furthermore, this research elucidates that the selection between anatase and rutile phases plays a vital role in the photostabilization. Functionalized Rutile TiO2 exhibited exceptional UV resistance, effectively inhibiting photodegradation; for example, after 15 days of exposure, the functionalized systems exhibited a 497.6% improvement for PLA/TiO2 R10 + 5% (22.1 ± 2.5 MPa), while the PLA/TiO2 R10 + 5% showed an 85.1% increase in composite stiffness (35.5 ± 3.5 MPa) after 7 days of degradation, in comparison with pristine PLA (19.2 ± 2.9 MPa). Anatase, conversely, displayed varying effects depending on concentration, acting as a stabilizer at lower levels and a promoter of degradation at higher concentrations. This knowledge enables the precise modifying of PLA composites for specific applications, balancing crystallinity, mechanical properties, and UV resistance for a diverse array of applications. Highlights: TiO2 enhances photostability in PLA confirming its potential as a UV stabilizer.Comparing anatase and rutile phase: Unveiling PLA composite dynamics.Glutaric acid on TiO2 enhances PLA composite strength significantly.Optimal acid concentration key to composite performance.Tailored PLA composites balance crystallinity, mechanics, and UV resistance. [ABSTRACT FROM AUTHOR]

Synthetic Janus micro/nanomotors can efficiently convert ambient energy into asymmetrical self‐propulsive force, overcoming random thermal fluctuations and enabling autonomous migration. Further modifications to the motors can equip them with different functional modules to meet different needs. However, developing a versatile and high‐yield fabrication method for multifunctional Janus micromotors remains challenging. In this study, a modular fabrication approach for micromotors with a particle‐tip structure based on the self‐focusing lithography induced by an array of TiO2 microspheres is presented. By adjusting the tip composition or loading, precise programming of motor functionality is achieved, allowing for various capabilities such as photoredox reaction‐induced propulsion, fluorescent imaging, electric and magnetic navigation. Furthermore, the flexibility of this fabrication method by selectively loading materials onto two tips is demonstrated to achieve multifunctionality within a micromotor unit. This study proposes a straightforward and versatile approach for modular functional micromotors. [ABSTRACT FROM AUTHOR]

The performance of Poly(lactic acid) (PLA) composites reinforced with functionalized titanium dioxide (TiO2) nanoparticles in rutile and anatase crystalline phases were systematically investigated. The results underline that the incorporation of TiO2, regardless of its crystalline structure, significantly enhances PLA's crystallinity by 85%. Notably, rutile TiO2, when functionalized with higher glutaric acid concentrations, was an effective crystallinity booster by 95%, passing from 20.39% to 39.58% crystallinity for the PLA/TiO2 R20 + 10% system. Furthermore, this research elucidates that the selection between anatase and rutile phases plays a vital role in the photostabilization. Functionalized Rutile TiO2 exhibited exceptional UV resistance, effectively inhibiting photodegradation; for example, after 15 days of exposure, the functionalized systems exhibited a 497.6% improvement for PLA/TiO2 R10 + 5% (22.1 ± 2.5 MPa), while the PLA/TiO2 R10 + 5% showed an 85.1% increase in composite stiffness (35.5 ± 3.5 MPa) after 7 days of degradation, in comparison with pristine PLA (19.2 ± 2.9 MPa). Anatase, conversely, displayed varying effects depending on concentration, acting as a stabilizer at lower levels and a promoter of degradation at higher concentrations. This knowledge enables the precise modifying of PLA composites for specific applications, balancing crystallinity, mechanical properties, and UV resistance for a diverse array of applications. Highlights: TiO2 enhances photostability in PLA confirming its potential as a UV stabilizer.Comparing anatase and rutile phase: Unveiling PLA composite dynamics.Glutaric acid on TiO2 enhances PLA composite strength significantly.Optimal acid concentration key to composite performance.Tailored PLA composites balance crystallinity, mechanics, and UV resistance. [ABSTRACT FROM AUTHOR]

The use of a photo-electrochemical cell (PEC) to produce hydrogen from wastewater is a promising innovation. In this context, this study investigates the impact of a pollutant on the photo-electrochemical properties of sol-gel synthesized TiO 2 and TiO 2 –Co 3 O 4 thin films for hydrogen production in a polluted electrolyte. Combining the photocatalytic properties of TiO 2 with the electronic properties of Co 3 O 4 offers an effective solution for achieving effective photo-electrochemical properties in polluted environments. Nevertheless, despite the lowest photocatalytic activity, the hybrid thin film TiO 2 –Co 3 O 4 with the highest Ti/Co ratio (1:0.5) shows the most promising performance with simultaneous 11.4 μmol cm−2 h−1 H 2 production and 12% acid orange 7 degradation after 3 h irradiation under xenon light without the use of any sacrificial agent. This indicates that the electronic conductivity provided by the presence of Co 3 O 4 is a critical property for achieving optimal performance in PEC coupling for hydrogen production and wastewater treatment. [Display omitted] • Sol-gel TiO 2 –Co 3 O 4 films enabled coupling of water splitting and remediation. • 11 μmol cm−2 h−1 H 2 was produced after 3h Xe irradiation without sacrificial agent. • Simultaneous 12% acid orange 7 degradation was measured. [ABSTRACT FROM AUTHOR]

A high entropy carbide (TaNbTiV)C was fabricated via spark plasma sintering of high entropy powders that were prepared using a molten salt method. The as-fabricated high entropy carbide was then investigated for its high-temperature oxidation behavior at 850 °C, under atmospheres with three different oxygen contents (20 vol%, 40 vol%, and 60 vol%). After the high-temperature oxidation process, the main phases observed in all the specimens were incompletely oxidized phase (Nb x Ti 1-x)C y O 2-y and oxides (Nb 0.5 Ta 0.5) 2 O 5 , TiO 2 , and Nb 2 O 5. Importantly, the thickness of the oxide layer initially increased and then decreased as the oxygen content increased. When the oxygen content reached 40 vol%, the ceramic displayed severe oxidation behavior with observed thicker of the oxide layer, as well as numerous pores and cracks in the oxide layer. This work provides new insights into the oxidation behavior of high entropy carbides. [ABSTRACT FROM AUTHOR]

Multiphase composites of lithium ceramics have emerged as a prominent area of research in the development of advanced solid tritium breeding materials. In this study, Li 2 TiO 3 /Li 2 SiO 3 co-doped Li 4 SiO 4 ceramic pebbles were prepared through an in-situ reaction between Li 4 SiO 4 and TiO 2. The objective of this study is to enhance the thermal cycling stability of Li 4 SiO 4 by impeding the grain boundary migration of Li 4 SiO 4 under high temperature conditions. The effects of the in-situ generated Li 2 TiO 3 /Li 2 SiO 3 particles on the microstructure, crush load and thermal cycling stability of Li 4 SiO 4 ceramic pebbles were investigated. The in-situ formed Li 2 TiO 3 and Li 2 SiO 3 particles effectively hindered the grain growth and minimized the formation of large intracrystalline pores in Li 4 SiO 4. At a sintering temperature of 900 °C, the Li 2 TiO 3 /Li 2 SiO 3 particles are beneficial in increasing the crush load of Li 4 SiO 4 ceramic. However, at lower sintering temperatures, their impact was counterproductive. An increase in the volume fractions of the Li 2 TiO 3 /Li 2 SiO 3 had a positive effect on grain refinement but a negative effect on crush load. The Li 2 TiO 3 /Li 2 SiO 3 co-doped Li 4 SiO 4 ceramic pebbles exhibited excellent structural stability during thermal cycling. The optimum mechanical stability was achieved at a TiO 2 addition of y = 0.1. The in-situ generated fine second phase particles effectively impeded grain boundary migration at high temperatures, providing a viable strategy for improving the thermal stability of Li 4 SiO 4 tritium breeders. [ABSTRACT FROM AUTHOR]

Calcium hexaaluminate (CaAl 12 O 19 , CA 6) has great potential for application in high-temperature industries. However, owing to its intrinsic hexagonal lamellar crystal structure, it is difficult to obtain calcium hexaaluminate materials with high densification. In this study, using a two-stage sintering method and TiO 2 sintering aid, the densification of calcium hexaaluminate materials (relative density >95 %) was achieved. The evolution behaviors of the phase composition and microstructure and the intrinsic sintering kinetics were investigated in detail. The results showed that the addition of TiO 2 promoted the formation of CA 6 grains with a more homogeneous morphology and an increased-density equiaxial morphology. The elevation of the sintering temperature the sintering temperature also facilitated the densification of CA 6 , as the growth rate of the CA 6 grains along the C-axis raised significantly with the sintering temperature. When 1 wt% of TiO 2 was added and the sintering temperature was 1750 °C, a CA 6 material with a bulk density of 3.61 g/cm3 (relative density over 95 %) could be fabricated. [ABSTRACT FROM AUTHOR]

Alumina (Al 2 O 3) ceramic is widely used in various industrial applications due to its excellent mechanical properties and environmental stability. 3D printing technology endows ceramic components with more design flexibility and manufacturing efficiency. However, the high sintering temperature of Al 2 O 3 (typically above 1600 °C) has hindered its integration with other functional ceramics or metals, thereby restricting its broader application. In this work, we developed a series of photosensitive Al 2 O 3 slurries with different sintering aids suitable for vat photopolymerization 3D printing. Optimal sintering temperatures of 1450 °C and 1250 °C for 3D-printed Al 2 O 3 ceramics were achieved by adding 3.5 wt% TiO 2 and 3.5 wt% CuO–Mg(OH) 2 –TiO 2 as sintering aids, respectively. We investigated the viscosities and curing behaviors of these Al 2 O 3 slurries, as well as the phase compositions, microstructures, and mechanical properties of Al 2 O 3 ceramics after sintering. Various cellular and lattice structures were fabricated by 3D printing to demonstrate their good printability and excellent mechanical properties. [ABSTRACT FROM AUTHOR]

α-Fe 2 O 3 as one of the most promising anode materials of lithium-ion batteries (LIBs) has many advantages including a high theoretical specific capacity, high operating potentials offering high safety, low synthetic cost, and environmental friendliness. However, Fe 2 O 3 suffers from rapid capacity fading caused by the huge volume change during charging and discharging processes. TiO 2 as an anode of LIBs has excellent structural stability. In the work, α-Fe 2 O 3 /TiO 2 composite has been synthesized via a one-pot solvothermal method. The combination of the two materials can produce complementary effects to make the composite have high specific capacities and good cycling performance. The TiO 2 can buffer the large volume variation of Fe 2 O 3 during cycling and prevent the Fe 2 O 3 particles from pulverization and aggregation. In addition, the effects of the solvothermal reaction time and the TiO 2 content on the physical and electrochemical performance have been researched in detail. The α-Fe 2 O 3 /TiO 2 -24-0.5 anode with the solvothermal reaction time of 24 h and the TiO 2 content of 22 wt% shows the best electrochemical performance. 711.2 mAh/g is obtained at 0.1 A/g for the sample. Cycling for 200 cycles, 510.7 and 450.1 mAh/g are obtained at 0.5 and 1 A/g, respectively. Moreover, α-Fe 2 O 3 /TiO 2 -24-0.5 as the anode is applied in the LiNi 0.5 Mn 1.5 O 4 //α-Fe 2 O 3 /TiO 2 -24-0.5 full cell, which can deliver 718.7 mAh/g at 0.5C in 1.7–4.6 V. The full cell can power different color light-emitting diode (LED) bulbs and light strings. This study presents the successful utilization of α-Fe 2 O 3 /TiO 2 in the full cells for the first time, showing the potential applications of the composite. [Display omitted] • TiO 2 with stable structure makes α-Fe 2 O 3 /TiO 2 anode have good cycling performance. • The α-Fe 2 O 3 /TiO 2 anode can combine the advantages of the Fe 2 O 3 and TiO 2 anodes. • α-Fe 2 O 3 /TiO 2 anode holds significant practical value in full cells. [ABSTRACT FROM AUTHOR]

Interest in self-cleaning coatings is rising due to their potential to enhance comfort and quality of life in polluted urban environments, driving the search for materials with optimal physical properties. Convergent with this goal, this study investigates the wetting properties and photo-catalytic efficiency of reticulated TiO 2 layers. It shows that these properties are significantly influenced by the topographical characteristics of the TiO 2 surface, which can be precisely controlled through variations in pulverization pressure and low-temperature post-annealing treatments. Post-deposition annealing of the TiO 2 layers achieves 100 % self-cleaning efficiency for both thick and thin films, with optical transmission ranging from approximately 60 %–80 % in the visible spectrum. Additionally, the TiO 2 layers exhibited promising capabilities for eliminating pathogenic microorganisms and disinfecting surfaces. The underlying causal factors of these remarkable and technologically promising surface features are explored and discussed. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride nanorods/titanium dioxide microspheres (g-C 3 N 4 NRs/TiO 2 MSs) Z-scheme heterojunctions were simply prepared by a one-step hydrothermal method, which showed improved visible-light-induced photocatalytic activity for the degradation of tetracycline hydrochloride (TC-HCl). The photodegradation activity of g-C 3 N 4 NRs/TiO 2 MSs is 6.6 and 1.9 times better than that of pristine g-C 3 N 4 and TiO 2 , which is assigned to the unique morphology and formed heterojunction. Hydroxyl radical (⋅OH) and superoxide radical (⋅O 2 −) were the main species for TC-HCl photodegradation according to capture experiments, and a possible mechanism is proposed. This study provides an effective reference for the preparation of binary heterostructures with excellent photocatalytic activity from a simplified process. Z-scheme g-C 3 N 4 NRs/TiO 2 MSs heterojunction was successfully constructed from the simple one-step process which shows enhanced photocatalytic activity and good stability for treating refractory tetracycline hydrochloride. The enhancement is assigned to unique morphology and the formed heterojunction which facilitates charge transfer and visible light absorption. [Display omitted] • Z-scheme g-C 3 N 4 NRs/TiO 2 MSs heterojunction was simply constructed by a one-step hydrothermal method. • TiO 2 microspheres were tightly attached to the surface of g-C 3 N 4 nanorods. • g-C 3 N 4 NRs/TiO 2 MSs (0.8:1) shows 6.6-fold higher TC-HCl degradation rate than g-C 3 N 4 NRs. • The improved activity is related to the unique morphology and heterojunction. [ABSTRACT FROM AUTHOR]

Background: The utilization of titanium dioxide nanoparticles (TiO2 NPs) has significantly increased across various industries. Objectives: This study rigorously explored the impact of TiO2 NPs exposure on chicken embryos, focusing particularly on alterations in the immune system, liver functionality and key biochemical markers. Methods: The study involved three groups of 30 eggs each, subjected to increasing doses of TiO2 NPs: Group C (control), Group T1 (150 µg/mL) and Group T2 (300 µg/mL). After 48 h of incubation, the eggs in Groups T1 and T2 each received an injection of 0.3 mL of the TiO2 NPs solution. In contrast, the eggs in the control group (Group C) were injected with 0.3 mL of saline solution. Histopathological changes were analysed using haematoxylin and eosin (H&E) staining, whereas amniotic fluid's biochemical properties were examined photometrically. The study also assessed the expression of immune genes (AvBD9, IL6 and IL8L2) through quantitative PCR. The evaluations included growth metrics, amniotic fluid biochemistry and histological analysis of the liver, caecal tonsil and bursa of Fabricius. Results: The results revealed subcutaneous haemorrhage, significant reductions in total body weight and marked changes in biochemical markers, including urea, creatinine, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in the amniotic fluid of the groups treated with TiO2 NPs, compared to the control. Histological examinations indicated noticeable alterations in the liver, caecal tonsil and bursa of Fabricius following TiO2 NP exposure. These alterations were characterized by disruptions in cellular structures and variations in lymphocyte counts. Furthermore, a notable decrease in the expression of immunity genes, namely, AvBD9, IL8L2 and IL6, was observed in the TiO2 NP‐treated groups compared to the control. Conclusion: The findings underscore the need for risk assessments of TiO2 NPs exposure due to its impact on development and immunity. Future research should explore its impact on neurodevelopment and degeneration. [ABSTRACT FROM AUTHOR]

Develop a sustainable bovine hydroxyapatite dental ceramic with the addition of titanium dioxide (TiO 2) nanoparticles (5 % and 8 % by weight), analyzing the outcome of this addition to the microstructure, as well as its mechanical and chemical properties, in order to evaluate whether they satisfy the International Organization for Standardization (ISO) 6872:2015 for dental ceramics or not. Disks were obtained through uniaxial followed by isostatic pressing from bovine hydroxyapatite powder and TiO 2 nanoparticles and sintered at 1300ºC for 2 h. Three experimental groups were developed (HA, HA+5 %TiO 2 and HA+8 %TiO 2) and subjected to X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), indentation fracture (IF), biaxial flexural strength (BFS) and chemical solubility test. XRD revealed, for HA group, the appearance of a peak corresponding to b-tricalcium phosphate (ß-TCP). For HA+ 5 %TiO 2 and HA+ 8 %TiO 2, the entire composition was converted into ß-TCP and calcium titanate (CaTiO 3). The SEM images showed a dense ceramic matrix and a uniform distribution of another phase in groups with TiO 2 nanoparticles. HA+ 5 %TiO 2 (1.40 ± 0.18 MPa.m1/2) and HA+ 8 %TiO 2 (1.32 ± 0.18 MPa.m1/2) showed significantly higher fracture toughness values than HA (0.67 ± 0.09 MPa.m1/2). HA showed significantly higher characteristic stress (295.8 MPa) in comparison to groups with 5 % (235.1 MPa) and 8 % (214.4 MPa) TiO 2 nanoparticles. Differences were not observed between the Weibull modulus values. The solubility results indicated that all experimental ceramics were above the 2000 ug/cm2 limit set by the ISO 6872:2015. This study proposed the development and characterization of a new ceramic for dental prosthesis made from HA extracted from bovine bones, with the intention of reusing these solids waste and transforming them into a sustainable and low-cost material. Although the experimental calcium phosphate ceramic with additions of 5 % and 8 % of TiO 2 achieved desirable mechanical properties, the chemical solubility values were very high. [Display omitted] • Bovine HA derived bioceramic with TiO 2 presents sustainability potential. • The addition of 5 % and 8 %TiO 2 significantly improved material's fracture toughness. • HA + TiO 2 bioceramic material converted microstructure to ß-TCP and CaTiO 3. • HA+TiO 2 achieved mechanical ISO standards, but failed chemical solubility limits. [ABSTRACT FROM AUTHOR]

AlN is a promising candidate for photonic integrated circuits. In this study, horizontally stacked transverse quasi‐phase‐matched (QPM) waveguides with an AlN center core and Si3N4, Ta2O5, and TiO2 side cores were designed to generate squeezed light at 920 nm. The squeezing level was calculated by considering the propagation loss at the wavelengths of the squeezed light and pump light. Using TiO2 for the side cores enhanced the electric field amplitude of the pump light in the AlN center core, and a high nonlinear coupling coefficient was obtained. Owing to the small propagation loss of the AlN waveguide on sapphire and high nonlinear coupling coefficient of the transverse QPM with TiO2 side cores, a squeezing level of over 8.1 dB was expected with a 1 cm long waveguide and pump power of 70 mW. [ABSTRACT FROM AUTHOR]

Exploiting the Bragg mirror effect of photonic crystal photoelectrode is desperately desired for photoelectrochemical water splitting. Herein, a novel TiO2 nanotube photonic crystal bi-layer structure consisting of a top nanotube layer and a bottom nanotube photonic crystal layer is presented. In this architecture, the photonic bandgap of bottom TiO2 nanotube photonic crystals can be precisely adjusted by modulating the anodization parameters. When the photonic bandgap of bottom TiO2 nanotube photonic crystals overlaps with the electronic bandgap of TiO2, the bottom TiO2 nanotube photonic crystal layer will act as a Bragg mirror, leading to the boosted ultraviolet light absorption of the top TiO2 nanotube layer. Benefiting from the promoted UV light absorption, the TiO2 NT-115-NTPC yields a photocurrent density of 1.4 mA/cm2 at 0.22 V vs. Ag/AgCl with a Faradic efficiency of 100%, nearly two times higher than that of conventional TiO2 nanotube arrays. Furthermore, incident photon-to-current conversion efficiency is also promoted within ultraviolet light region. This research offers an effective strategy for improving the performance of photoelectrochemical water splitting through intensifying the light–matter interaction. [ABSTRACT FROM AUTHOR]

This study presents a comparative analysis of anodization and hydrothermal techniques for synthesizing TiO2 nanotubes directly on titanium foil. It emphasizes its advantages as a substrate due to its superior conductivity and efficient charge transfer. Optimized synthesis conditions enable a thorough evaluation of the resulting nanotubes' morphology, structure, and optical properties, ultimately assessing their photoelectrochemical and photocatalytic performances. Scanning electron microscopy (SEM) reveals differences in tube diameter and organization. An X-ray diffraction (XRD) analysis shows a dominant anatase (101) crystal phase in both methods, with the hydrothermally synthesized nanotubes exhibiting a biphase structure after annealing at 500 °C. UV–Vis and photoluminescence analyses indicate slight variations in band gaps (around 0.02 eV) and recombination rates. The anodized TiO2 nanotubes, exhibiting superior hydrophilicity and order, demonstrate significantly enhanced photocatalytic degradation of a model pollutant, amido black (80 vs. 78%), and achieve a 0.1% higher photoconversion efficiency compared to the hydrothermally synthesized tubes. This study underscores the potential advantages of the anodization method for photocatalytic applications, particularly by demonstrating the efficacy of direct TiO2 nanotube growth on titanium foil for efficient photocatalysis. [ABSTRACT FROM AUTHOR]

The European Commission (EC) has tasked the European Medicines Agency (EMA) to provide a recommendation towards the acceptability of titanium dioxide (TiO 2) in pharmaceutical products by early 2024 to inform on final decision in early 2025[1]. Unlike the already implemented ban of TiO 2 in foods, removing this excipient from pharmaceutical products will likely have significant impact on the pharmaceutical industry, regulatory agencies, and patients. This commentary explores the challenges facing the pharmaceutical industry tasked with supporting the development and registration of TiO 2 free (TF) drug products. Specifically, justification of formulation changes and potential impact to in vitro and in vivo performance, as well as differences in global regulatory comparative dissolution requirements to justify changing to TF drug product are discussed. Particularly, the uncertainties around how a formulation change such as removal of TiO 2 from immediate release solid oral dosage forms will be viewed in Europe compared to other regions is discussed. To respond to these challenges and avoid disruption to the medicines supply chain in case in vitro data such as dissolution is either too challenging or insufficient to justify changing to TF product, pharmaceutical companies may have to decide if the level of risk is worth the effort needed to reformulate, develop, and register a new TF product. [ABSTRACT FROM AUTHOR]

The 2D Ti3C2Tx MXene has a large specific surface area, abundant functional groups, and low work function, which has potential in the field of photocatalytic materials. However, the manufacturing of controllable films with high photocatalytic properties and desirable transmittance is a challenging task. Herein, low‐cost, large‐scale, and rapid preparation of Ti3C2Tx/TiO2 flexible composite films have been successfully prepared by inkjet printing technology, which can be applied in complex and special environments, as well as in photoelectrically controllable places for photocatalytic performance. With the increase of the anatase TiO2, the transmittance of Ti3C2Tx/TiO2 films increases from 55.37% to 73.27% at 780 nm, corresponding to the square resistance of 1.112–206.496 kΩ sq−1 and the figure of merit of 0.48–0.005. When the amount of anatase TiO2 is 15%, the film has the best photocatalytic effect on methylene blue (MB) dye, reaching 68.94%. After five cycles of testing, the degradation efficiency of MB dye decreases by only 5.68%, showing that the film has good cycling stability. This work provides a new research direction for photoelectrically controllable photocatalytic degradation in complex and special environments. [ABSTRACT FROM AUTHOR]

Polymer film capacitors experience a sharp decrease in charge–discharge efficiency and energy density under high‐temperature environments, which remains an urgent issue to address. In this article, atmospheric pressure plasma jet (APPJ) is used to deposit TiO2 to improve the energy storage performance of biaxially oriented polypropylene (BOPP) film in high‐temperature environment. The APPJ uses argon as the working gas and adopts a multielectrode grounding configuration to obtain the stable jet state. The precursor solution is prepared using tetraethyl titanate (TET) mixed with ethanol in a ratio of 5:3. The results show that the charge–discharge efficiency and discharge energy density (from 3.1 to 5.7 J cm–3) of BOPP films deposited by APPJ are improved at 120°C. [ABSTRACT FROM AUTHOR]